Range Loss Over Time, What Can Be Expected, Efficiency, How to Maintain Battery Health

[ro_explorer]

Haven't wrote here in a while. I'm one of the unlucky when it comes to battery.
When it was brand new in June 2021, my LR 2021 had 79.1kwh reported in SMT. Now, 8 months and 20.000 km later SMT is showing 74.6 KWh as nfp. To me this looks like on the far left of the degradation distribution for model 3 fleet.

I charged at 80% most of the time, going above that only right before going on a long trip. 75% of time I've charged at AC stations, with few supercharger sessions in between.

Not all batteries are created equal .

This week I've done a looong trip (1500 Km) and I was curious to see the impact of the supercharging sessions over my poor, degraded battery ...
I was in shock after seeing the numbers from SMT (I still am, in a good way):

What? When? How? Why? ... I was pretty convinced that from 74.6 will not bounce back more than 75 (which it did for a few weeks). Now, if this 77.1 value is correct, it means that my 9 months old, 24.000 Km Model 3 LR has only degraded 2.5% which is exactly spot-on as the expectations.

My question is, how the hell the BMS is not showing this value? For the past 2 months I charged randomly, AC only, not lower than 30% and only up to 70% .
This, combined with a mild spring weather, with temps hovering between 5 and 10 degreed Celsius.

 

[dhrivnak]

This week I've done a looong trip (1500 Km) and I was curious to see the impact of the supercharging sessions over my poor, degraded battery ...
I was in shock after seeing the numbers from SMT (I still am, in a good way):

View attachment 785609

What? When? How? Why? ... I was pretty convinced that from 74.6 will not bounce back more than 75 (which it did for a few weeks). Now, if this 77.1 value is correct, it means that my 9 months old, 24.000 Km Model 3 LR has only degraded 2.5% which is exactly spot-on as the expectations.

My question is, how the hell the BMS is not showing this value? For the past 2 months I charged randomly, AC only, not lower than 30% and only up to 70% .
This, combined with a mild spring weather, with temps hovering between 5 and 10 degreed Celsius.

When you do not charge above 85% the BMS does not have a chance to balance cells. And you will be sonstraned by the weakest cell. Also not driving below 30% the BMS loses sight of the true bottom end and is conservative. I assume on your trip you charged higher and drove lower allowing the BMS to calibrate.

 

[ro_explorer]

I assume on your trip you charged higher and drove lower allowing the BMS to calibrate.

You assumed right: In my trip the minimum I went down was 3% (once - usually I was stopping to a SC at around 15%) and the maximum was 95% (when I had a longer lunch than anticipated). But I did this kind of calibration in February as well (intentionally), and the BMS only reported 75.2 I think.

In my February calibration I charged to 100% and let the car connected for about 1H after it reached 100%, then I drove immediately down to 85%, them slowly , about 10% every day, until it reached 5%. I left the car sleep overnight at every ~10% decrease in capacity so the BMS had all the time in the world to calibrate. Still, now, out of the blue : more NFP numbers. I know these are just estimates but all I want to monitor is the actual battery degradation. Considering the global situation and the dark future of materials for the car industry, plus inflation and increase in prices, I'm actually considering keeping this car longer than the original leasing period of 3 years, maybe even buying it once the leasing expires.

 

[AAKEE]

When you do not charge above 85% the BMS does not have a chance to balance cells. And you will be sonstraned by the weakest cell. Also not driving below 30% the BMS loses sight of the true bottom end and is conservative. I assume on your trip you charged higher and drove lower allowing the BMS to calibrate.

I charge to 55% and usually drive down to 25-35% daily, no problem with the balance, I have mostly 4mV imbalance after weeks at no higher than 55%.

I also have full range after 15months/36.000km so it does not put me in a conservative BMS battery capacity.

 

[dhrivnak]

I charge to 55% and usually drive down to 25-35% daily, no problem with the balance, I have mostly 4mV imbalance after weeks at no higher than 55%.

I also have full range after 15months/36.000km so it does not put me in a conservative BMS battery capacity.

And I am speaking after 4 years and 78,000 miles. My previous Tesla I drove over 9 years.

 

[TrueTechData]

Does anyone know if there is any difference in charging at 120V 16A 50 Hz vs 60 Hz? I know the difference will be small (if any) but I have both options available to me at the push of a button so I thought it'd be worth an ask even if the difference is only like 1% or something.

 

[Candleflame]

When you do not charge above 85% the BMS does not have a chance to balance cells. And you will be sonstraned by the weakest cell. Also not driving below 30% the BMS loses sight of the true bottom end and is conservative. I assume on your trip you charged higher and drove lower allowing the BMS to calibrate.

there is no evidence that the model 3 does not balance cells below 85%.

 

[dhrivnak]

there is no evidence that the model 3 does not balance cells below 85%.

True, as Tesla gives very few details. But all lithium cells exhibit a very flat voltage curve between 20% and 80%. It is very hard to determine charge level unless cells are at a very low of very high state of charge. We saw this a lot with the Roadster that was able to show us a lot more detail including the balancing screen so we could see in detail what is going on. Nothing in the Model 3 changes the basic charge characteristics of a lithium battery. I have been working with lithium batteries for over 13 years now. I have built 2 plug in hybrids and 2 full EV's. And I have been driving a Tesla since early 2011. So unless you are an engineer with some deep battery knowledge be careful expousing what you do or do not know.

 

[Candleflame]

Does anyone know if there is any difference in charging at 120V 16A 50 Hz vs 60 Hz? I know the difference will be small (if any) but I have both options available to me at the push of a button so I thought it'd be worth an ask even if the difference is only like 1% or something.

doesnt really make any difference for you and is just the arbitary swing sweed for the electrons in AC...

I wasnt aware that americans could choose. 50hz is usually 220/230/240V and 60hz is 110 volts...
technically the smaller the better but aint no way you gonna notice this....

 

[Candleflame]

True, as Tesla gives very few details. But all lithium cells exhibit a very flat voltage curve between 20% and 80%. It is very hard to determine charge level unless cells are at a very low of very high state of charge. We saw this a lot with the Roadster that was able to show us a lot more detail including the balancing screen so we could see in detail what is going on. Nothing in the Model 3 changes the basic charge characteristics of a lithium battery. I have been working with lithium batteries for over 13 years now. I have built 2 plug in hybrids and 2 full EV's. And I have been driving a Tesla since early 2011. So unless you are an engineer with some deep battery knowledge be careful expousing what you do or do not know.

there are people who keep their battery for weeks at <60% and have no issues with balance.

 

[dhrivnak]

there are people who keep their battery for weeks at <60% and have no issues with balance.

I agree weeks do not matter. But months and years do. Cells falling out of balance is a very slow but real process. That is why Tesla and most other EV makers have invested so much in BMS systems and why EV builders often use them.

 

[Benjamez]

Hey guys super new to Tesla / EV.

Just bought a 2019 Model 3 standard plus and when I charge it at home it says that at 100% it can only do 195 miles of range?

Also, I’ve only been charging it up to 90% each night and not going below 20% driving.

Does that seem low or am I looking at the wrong spot?

Any tips?

 

[cwerdna]

If How I Recovered Half of my Battery's Lost Capacity is accurate, there could be calibration issues esp. if you use sentry mode coupled w/not sometimes charging to 100%.

 

[Benjamez]

If How I Recovered Half of my Battery's Lost Capacity is accurate, there could be calibration issues esp. if you use sentry mode coupled w/not sometimes charging to 100%.

Haven’t charged it up to 100% yet and we don’t have sentry mode turned on, but can charge it to 100% and try the calibration to see.

Anyone have a 2019 M3 S+ and can let me know what theirs says at 100% total mile range?

I understand things like higher speeds, AC, and all that come in to play whilst driving BUT I’m wondering why it shows so low even beforehand.

 

[Bouba]

While the BMS always gives different results...the effect is scientifically predictable....and range from..

Please don’t let that be true...
Oh no...
Phew!
Not bad..
Nice..
All right!

 

[FlatSix911]

Hey guys super new to Tesla / EV.
Just bought a 2019 Model 3 standard plus and when I charge it at home it says that at 100% it can only do 195 miles of range?

Also, I’ve only been charging it up to 90% each night and not going below 20% driving.
Does that seem low or am I looking at the wrong spot?
Any tips?

Which Model 3 variant?

 

[Benjamez]

Which Model 3 variant?

Standard plus

 

[Candleflame]

You assumed right: In my trip the minimum I went down was 3% (once - usually I was stopping to a SC at around 15%) and the maximum was 95% (when I had a longer lunch than anticipated). But I did this kind of calibration in February as well (intentionally), and the BMS only reported 75.2 I think.

In my February calibration I charged to 100% and let the car connected for about 1H after it reached 100%, then I drove immediately down to 85%, them slowly , about 10% every day, until it reached 5%. I left the car sleep overnight at every ~10% decrease in capacity so the BMS had all the time in the world to calibrate. Still, now, out of the blue : more NFP numbers. I know these are just estimates but all I want to monitor is the actual battery degradation. Considering the global situation and the dark future of materials for the car industry, plus inflation and increase in prices, I'm actually considering keeping this car longer than the original leasing period of 3 years, maybe even buying it once the leasing expires.

your car has hardly any degradation to start with. Some fluctuations in range is normal. just charge to 100% and then drive down to 10% 5% or 0% and have a look at your voltage. That will tell you the true range of your battery....

 

[TrueTechData]

doesnt really make any difference for you and is just the arbitary swing sweed for the electrons in AC...

I wasnt aware that americans could choose. 50hz is usually 220/230/240V and 60hz is 110 volts...
technically the smaller the better but aint no way you gonna notice this....

I have a 2 kWh Bluetti battery pack that I use as the interface between my 700W solar panels and my car. The Bluetti lets me choose 50 Hz or 60 Hz output and the Tesla charger works with either one, so I thought I'd ask.

More deets if interested:

I currently charge from the Bluetti at 16A 120V. I start charging when the Bluetti gets near 100% charge - it allows both charge from my solar, and discharge to charge my Model 3 simultaneously. The Bluetti reaches full charge around 1:30 PM with a few hrs of good sun left. It charges my car at 1850W, and I can generally sustain ~600W input from solar throughout the charge, so the net wattage of the Bluetti throughout the charge is about -1250 W, and it is a 2kWh pack, which means with the press of one button a day (turning on the AC output of the Bluetti) I get approx 3 kWh daily right now. By the time the single charge cycle is complete, there is still some sun left, so I have to start the discharge of the Bluetti a little earlier each day. Which means I'm getting a little bit more than that 3kWh daily, as I have to start the discharge a little bit earlier each day to not let it reach 100%.

I expect towards summer I will be able to get closer to 3.5-4 kWh daily with this setup. It covers virtually all of my daily driving.

Since it is a limited setup, that is why I was curious about 50/60 Hz as I'm trying to pull as much as possible from the Bluetti, even if it is a small amount different

 

[frodebh]

When you do not charge above 85% the BMS does not have a chance to balance cells. And you will be sonstraned by the weakest cell. Also not driving below 30% the BMS loses sight of the true bottom end and is conservative. I assume on your trip you charged higher and drove lower allowing the BMS to calibrate.

How long do you need to sit above 85% for the cells to balance, ballpark hours figure?